1. Field of the Invention
The present invention relates to a generative production method for producing a component by the repeated, consecutive selective melting and/or sintering of a powder by means of a quantity of heat introduced by beam energy, such that the powder particles fuse and/or sinter in layers. In addition, the present invention relates to a corresponding powder and also to a component produced therefrom.
2. Prior Art
An extremely wide variety of methods are known from the prior art for rapidly producing a component. In addition to what is termed three-dimensional printing (3D printing), there are beam methods, such as electron beam melting, selective laser melting, selective laser sintering, and many other methods, for example stereolithography or casting methods and the like. Although primarily prototypes can thereby be generated in a very rapid manner, the methods actually differ in principle.
DE 11 2005 002 040 T5 discloses, for example, a rapid prototyping method for producing aluminum/magnesium alloys by means of a 3D printing method. In this method, the aluminum/magnesium particles are firstly joined to one another by means of a binder to form the prototype in the printing method and then sintered, such that the prototype is formed. Since the aluminum and/or magnesium alloys are very susceptible to oxidation, the corresponding powder particles are protected by a metal layer made of, for example, copper. However, such a method is limited to low-melting materials, since, in the case of high-melting materials, the prototype as a whole has to be exposed to very high temperatures over a long period of time in order to achieve a sufficient sintered join.
US 2006/0251535 A1 discloses a further method, in which three-dimensional prototypes are formed from coated powder particles by binder-assisted printing. The coating of the particles which is made of binders and sinterable materials serves to make joining of the powder particles to one another possible in that the coatings or parts thereof fuse, weld or sinter to one another in order to thus form corresponding bridges between the powder particles.
The disadvantage of these methods, however, is that the properties of the prototype differ greatly from the actual workpiece, since the particles are not directly themselves joined but rather are “adhesively bonded” to one another by way of the binders and/or sinter materials.
Although this method would afford the possibility to produce a prototype with relatively little use of heat and energy for high-melting materials, i.e. in particular high-temperature materials, the result is unsatisfactory, since the properties, in particular the mechanical properties, of the prototype differ greatly from those of the later workpiece.
When beam-assisted methods, i.e. for example laser beam methods or electron beam methods, are used for the production of prototypes from high-melting materials, there is additionally the problem that such a high quantity of heat has to be introduced into the powder or into the surface of the already formed prototype, in order to make fusion or sintering possible, that high temperature gradients which can lead to cracking arise. If, however, cracks are made in the prototypes, in such a case, too, the mechanical properties differ considerably from the actual workpiece, and therefore this too is disadvantageous.